You are absolutely right. Did you watch any of this game? He's got some nice potential. Most of his points came from the line and he struggled to finish against bigger guys inside as Fishy alluded to earlier. He's also going to learn that he has to play hard and play defense if he wants to see any time. His coach let him and his teammates get away with a lot of loafing and a lot of lackadaisical play.
I don't disagree that he's got a lot to learn but I think you watched the state championship game and got way too down on this kid off that. I'm sure he and his team were completely charged up, they came out and got pressed, found themselves in a rout in the blink of an eye, and things spiraled downhill. It happens, and to evaluate a player off that kind of game is kind of like evaluating Bobby Hurley off the 1990 title game. The other game you posted is from Thanksgiving, when he had just started with a new team and there was no chemistry at all - that's the period where Buford took most all of their losses for the year.
We haven't seen video from the state quarterfinal game where Lubin went for a double double with 30 plus, and we haven't seen video from the state semifinal game where he scored 19 in the fourth quarter (!) as part of a 37 point night to get to the finals. He must have been playing pretty darn hard then.
The kid was the Georgia AAA player of the year and the winning team's MVP of the AAA all star game for good measure. As a post player. In an All Star game.
You're completely correct that he's not going to come in and be a star or, almost certainly, even a starter. You and Fishy are also correct that he plays under the rim and learning to score down low will take some time.
But this kid was clearly doing a lot of things right down in Georgia this year, pretty much every kid needs to learn to play harder in transitioning from high school to college, and this particular kid committed after watching our famed hellacious first practice of the year.
So I think he's got a pretty good ticker, I think he's got talent, and I think he's going to help us next year.